In recent years, particular attention has been paid to the comfort of an individual that operates construction equipment. To that end, environmentally protected cabs have been developed to insure the comfort of an operator through the provision of heating and air conditioning systems. However, even with the provision of air conditioning, on many vehicles the positioning of the cab is such that it is mounted next to a source of heat such as an engine compartment. The heat generated by the engine is often trapped within the confines of an enclosure and thus serves to increase the temperature of surrounding structures such as the cab thus counteracting the effect of the air conditioning unit. In many instances, a cab wall will be the only barrier between an engine compartment and the inside of the cab which will result in the direct transfer of heat into the cab.
A system that provides for the cooling of an engine compartment as well as an adjacent compartment is typically shown in U.S. Pat. No. 3,866,580, issued to Whitehurst, et al, and is assigned to the assignee of this application. Cooling air for the engine enclosure is drawn through air ducts in panels located at the rear and along the sides of the vehicle. Movement of the air occurs as a result of a pressure differential that is created by a venturi-type relationship between the engine exhaust pipe and a surrounding tubular encasement. Similarly, air is drawn through air ducts in panels surrounding the compartment that houses the radiators which is positioned just forward of the engine compartment. The air is drawn through the compartment in conventional fashion by a fan and is directed through exhaust ducts in the front panels of the compartment. While this patent discloses an effective way of removing heat from within an enclosure housing a heat producing component, it does not address a method of preventing the transfer of that heat to adjacent enclosures.
U.S. Defensive Publication No. T986,006, issued to Gerald P. Simmons, is also assigned to the assignee of this invention and discloses an air circulation system for a vehicle cab. In this system outside air is drawn through the cab by a venturi flow created between the exhaust pipe of the engine and the tubular structure that houses it. Alternatively, air may be drawn through the cab by an engine driven fan that is normally associated with the radiator and engine cooling system. Here again, this design provides only a system which circulates air within the cab and does not address the prevention of heat transfer between two compartments.
The present invention is directed to overcoming one or more of the problems as set forth above.